Big Ideas Math Algebra 1, 2015
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Big Ideas Math Algebra 1, 2015 View details
6. Arithmetic Sequences
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Exercise 36 Page 215

What is the first term of the sequence? What is the common difference? Use these values in the explicit equation for arithmetic sequences.

Equation: a_n=10n+90
a_(10): 190

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Explicit equations for arithmetic sequences follow a specific format. a_n= a_1+(n-1) d In this form, a_1 is the first term of the sequence, d is the common difference, and a_n is the nth term. In the given arithmetic sequence, the first term is a_1= 100. Let's observe the other terms to determine the common difference d. 100+ 10 âź¶110+ 10 âź¶120+ 10 âź¶130 + 10 âź¶ ... The common difference is d= 10. By substituting these two values into the explicit equation and simplifying, we can find the formula for this sequence.
a_n=a_1+(n-1)d
a_n= 100+(n-1)( 10)
a_n=100+10n-10
a_n=10n+90
This equation can be used to find any term in the given sequence. To find a_(10), the 10th term in the sequence, we substitute 10 for n.
a_n=10n+90
a_(10)=10( 10)+90
a_(10)=100+90
a_(10)=190
The 10th term in the sequence is 190.